Nursing behavior and early development of impala at San Diego Wild Animal Park

Because impala are commonly exhibited and handreared in zoos and their natural nursing behavior had not previously been studied, we examined nursing and early development in five impala calves housed in a large, naturalistic enclosure. Calves were observed for the first 5 weeks of life during 12-hr continuous watches and 20-min focal animal samples. Total daily suckling time decreased while time grazing and feeding on concentrates increased from 1–5 weeks of age. An increasing proportion of nursing bouts were terminated by the dam as calves matured, with dams terminating almost 70% of bouts during the first week. Suckling success and maternal grooming also decreased after week I, suggesting that impala mothers cut back early on nursing and grooming of offspring. Rapid decline in mother-young spatial proximity and a concomitant increase in calf association with age-mates over time suggests that the mother-young bond is weak and ephemeral in impala. An example of the implications of our results for improving handrearing programs would be that newborn calves should be started on a daylight feeding schedule of one bottle-feeding every three hours, and that they not be allowed to gorge themselves at any one of these feedings.